Hermetically sealed power generator



Oct. 30, 1962 H. H; HUMPAL EERMETICALLY SEALED PowER GENERATOR 2Sheets-Sheet 1 Filed April 21, 1958 HERMETICALLY SEALED POWER GENERATORFiled April 2l, 1958 2 Sheets-Sheet 2 United States Patent liiice3,661,733 Patented ct. 30, 1952 Ohio Filed Apr. 21, 1958, Ser. No.729,785 Claims. (Cl. 2902) The present invention relates to improvementsin power plants and particularly to an improved mechanism having a primemover which is capable of unattended continuous operation on a Rankinecycle.

An object of the inventinon to provide a closed prime mover in a gassystem which eliminates all seals and, therefore, eliminates anypossible leakage paths.

Another object of the invention is to provide an improved power plantwherein all moving components are mounted .on a single shaft and sealedin a single housing with no parts connected to the outside of thehousing to have relative movement.

A further object is to provide an improved power plant unit whichemploys a single working iiuid for a plurality of functions such asoperating the prime mover, cooling component parts, lubricating thebearings, etc.

Another object of the invention is to provide a power mechanism havingan improved lubrication system.

A further object of the invention is to provide a complete sealed powerplant unit with an improved iluid flow system.

A still further object of the invention is to provide an improved powerplant assembly producing an electrical energy output with improved heattransfer arrangements.

Other objects and advantages will become more apparent with the teachingof the principles of the invention in connection with the disclosure ofthe preferred embodiments in the specification, claims and drawings, inwhich:

FIGURE l lis an elevational view shown partly in schematic form of thepower plant -assembly embodying the principles of the present invention;and

FIGURE 2 is a detailed sectional view taken through the housing for thepower plant and with parts of the system shown in FIGURE l removed forclarity of illustration.

As shown on the drawings:

The power plant assembly is shown substantially in its entirety in FGUREl and various sections are indicated by labels. The moving parts of themechanism are all enclosed within a sealed housing 4. The housing isformed of cast iron or the like with the various parts held together insealed relationship and with all of the moving parts contained within.The only openings from the sealed housing i consist of the passages forconnection of `conduits for lthe flow system for the working fluid, andleads for delivering electrical energy from the electrical generatorportion of the power plant.

As Iillustrated in FIGURE 2, the housing 4 may be formed of a casting orIthe like having a head end part 6 which is somewhat cylindrical in formto enclose the coils of an alternator 8, as also shown in FIGURE l.Adjacent the housing part 6 is a part 1i) with chambers formed thereinto enclose the turbine 12, and a circulating pump 14 which is alsoindicated as the main pump. The housing parts 6 and it) are respectivelyprovided with annular flanges 13 and l5 and these flanges have axiallyaligned holes to receive bolts such as I6 for clamping the housing partstogether. An annular seal 18 is provided to positively seal the partsand prevent leakage from the interior.

In placing all of the moving parts within the housing 4 and in providingabsolute seals, leakage to the atmosphere is positively prevented. Thisis essential to use in certain environments and the Rankine cycle uses amercury vapor turbine making a seal essential for maintenance of aclosed cycle for the operation and for protecting personnel. Theprevention of leakage is achieved with the arrangement of the presentinvention and this is also essential in certain uses wherein the workinguid may attain radioactive properties. An important use of thecontinuous operating self-contained power plant of the present inventionis found wherein heat for the working fluid is obtained from atomicallyactive material.

The part itl of the housing 4 is joined to a part 29 which houses acoolant pump 22. Parts l0 and Ztl have annular anges 24 and 26,respectively, provided with aligned axial holes to receive `bolts 2S forclamping the parts together. An annular sealing ring lfd) is providedbetween the parts.

Adjoining the housing part 2t) is an end housing part 32 and the partsare provided with annular flanges 34 and 36, respectively. Aligned holesin the iianges receive bolts 3S to clamp the parts together and gasketmeans may be provided between the parts to seal the chamber formedtherein. The part 2;@ coacting with the part 32 form m accumulator 4t)therein and the accumulator includes an accumulator chamber 42 and a gaschamber 44. The chambers are separated by a diaphragm wall 46 whosefunction will be described later.

The alternator S is provided with coils 47 and suitable electricalterminals lead through the housing part 6 and connect to a line 4Sleading to an electrical load S0. The turbine 12 is provided with arotor with a permanent magnet head 52 to cause the generation ofelectricity in a well known manner and the generator or alternator is ofthe type known as a radial gap alternator.

The generated electricity is delivered to the electrical load Sii andthe total load may be controlled in various ways such as by a parasiticload control 53 having a parasitic load bank S4. This obtains a constantload on the alternator S for constant speed operation. The electricalload Sti is provided with means for cooling in accordance with thepresent invention in a manner which will later be described. Thealternator is also cooled and for this purpose has a jacket which isformed as a part of the sealed housing Li, and has an inlet line S6 forcooling fluid and an outlet line 5S for cooling fluid.

A feature of the present invention is the utilization of the same fluidas used for the working iiuid for purposes of cooling units of the powerplant, as will be fully described.

The turbine 12 includes a turbine rotor 6) with turbine blades 62arranged around the outer periphery in the usual manner. The rotary`turbine blades 62 coact with stationary turbine blades 64 mounted onthe inside of the hollow housing part itl which forms a turbine charmber 66 therein. Leading from this chamber is a turbine exhaust passage68 to which is connected a turbine exhaust line 70.

ln the form of the invention disclosed as a preferred embodiment, theturbine is designed to operate on a mercury vapor cycle. The exhaustline 70 will thus be carrying mercury vapor and leads to a condenser'72, FIGURE l.

The turbine rotor dit is mountedon a power shaft 74. The power shaft 7dis shown supported on a rotary bearing 76 at its head end, and on arotary bearing 73 at the other end. The rotary bearings may be of anysuitable type which can operate under the conditions imposed by the hightemperatures of the working fluid and are illustrated as sleeve bearingswith appropriate passageways for conducting lubricating iluid.

As illustrated by the bearing 76, the bearing includes a sleeve 8bmounted in a collar S2 secured, such as by bolts 84, within the housingpart 16. The sleeve has an annular groove be in its outer surface withradial passageways S8 leading to the bearing surface between the shaftand sleeve. An axial passage @il leads through the bearing sleeve toopen to the intake pressure of a feed pump 14. Lubricating duid deliveryto the bearing is obtained through a passage 94 leading through thecollar 82 from the discharge of the feed pump 14.

Leakage from the bearing in the other direction causes the lubricatingHuid to engage a slinger ring 96 with the lubricant being thrownoutwardly in a chamber 98 at the head end of the turbine rotor 60. Theturbine chamber 9S slopes in a downward direction, when the housing ispositioned with its axis substantially horizontal, so that thelubricating iluid will run downwardly past the turbine rotor 60 and intothe turbine chamber 66 to ilow through the exhaust passage d of theturbine. Inasmuch as the working uid is used also as the lubricatingfluid, this lubricating fluid will continue to circulate and joins themercury exhaust vapor from the turbine.

The pump 14 is also mounted on the power shaft 74 and includes a pumpimpeller 11N) discharging into a volute chamber 102 which communicateswith a pump discharge passage 104 leading through the housing part 1d.The intake of the pump is through a passage 106 also leading through thehousing part 10. A pump intake line 108 connects to the intake pasage166 for the pump and a pump discharge line 110 connects to the dischargepassage 104 for the pump. The bearing 78 at the rear end of the powershaft 74 also includes a sleeve 112 rotatably supporting the shaft. Thesleeve is mounted in the housing part and has an annular groove 114 onits outer surface communicating with the lubricating supply passage 116which supplies lubricating lluid from a coolant pump 22. The bearingsleeve 112 has radial passages 120 leading from the groove 114 tolubricate the inner surface of the sleeve Ion which is supported thepower shaft 74. Axial passages 122 lead from the radial passage 120 toopen to a slinger ring 124 which also catches the leakage from thebearing and throws it into an intake chamber 126 for the circulatingpump 92. Leakage in the other direction along the shaft iiows into theintake of the coolant pump 11S.

The coolant pump 22 includes a rotor 127 mounted on the power shaft 74and is supplied through an inlet passage 128 and discharges through avolute chamber 131 which communicates with an outlet passage 152.Coolant fluid flows into passage 128 through a line 134, FIGURE l, andflows out through the pump discharge passage 132 through a line 136.

At the left end of the housing 4, as shown in FIG- URE 2, is theaccumulator. The accumulator chamber 42 is provided with a flow passage,not shown, which connects to a make-up control line 138. This linesupplies working iluid to the system to provide make-up working fluid tothe boiler-turbine combination, to the 'cooling system and to thelubricating system. The working uid is maintained at a static pressurein the make-up control line 13S by the movable bellows wall 46 which ispart of an expansible annular bellows wall 140 and which backs againstthe gas chamber 44.

The housing 4 contains all of the moving parts within and opens only forpassages for conducting the working fluid. As illustrated in FIGURE l,the working fluid leaving through the exhaust line 7@ of the turbinepasses into the condenser 72 and is condensed from a vapor to a liquid.A temperature control device 142 is provided to sense the temperature ofthe liquid leaving the condenser and to control operation thereof. Thecondenser preferably will be of the air cooling type in order that themechanism may be best adapted to unattended continuous operation. Thecondensed liquid leaves the condenser through a line 1118 and is pumpedup to a boiler unit 144 by the main pump 14. The line 110 leaving themain pump 14 leads to the boiler 144 through a pressure regulator 146which controls the pressure differentials for the high and low side ofthe Rankine cycle turbine 12.

The boiler 144 is provided with a supply of heat and for unattendedcontinuous operation may be heated by atomic heat sources. The heatedworking fluid leaves the boiler 144 through a line 148 to enter an inletpassage 159 leading to the turbine. Make-up working fluid is supplied tothe line leading to the boiler through a line 15) which leads from amake-up control 152 supplied by the line 138 leading from theaccumulator. Another line 154 leads from the make-up control to the line1118 leading from the condenser 72 to the mainrpump 14. p

rfhe working fluid is also used as a coolant. For this purpose thecoolant pump 22 circulates the coolant through a line 136 which connectsto a line 56 to circulate the coolant through the alternator orgenerator 8. A branch line 155 also leads from the line 136 to a heatexchange unit, not shown, which is part of the electrical load 50.Return from the electrical load is through a line 156 to the line 134back to the coolant pump 22. Flow through this return line 134 is cooledby a cooling unit 158 which is controlled by a temperature control unit160. While other types of coolant might be employed, mercury ispreferred to prevent accidental contamintu tion of the lluids throughbearing leakage.

In operation of the power plant, the working fluid is heated in theboiler unit 144 and, being preferably in the form of mercury, isdelivered as a vapor to the turbine 12 to drive the turbine rotor 60.The rotor carries the permanent magnet head 52 to operate the generatoror alternator 8 and supply electricity through leads 4S to theelectrical load 50i. The mercury vapor exhausts through a line 70 and iscondensed in the condenser 72 to be re turned by the main pump 14 to theboiler through the pressure regulator 146. Makeup working fluid issupplied through a line 138 leading from the accumulator chamber 42 ascontrolled by the make-up control 152. Another line 154 also conductsmake-up iluid to the circuit by being connected to the line 108. Themain pump 14 is driven by the power shaft 74 which also carries theturbine rotor 60 and the coolant pump rotor 127. The coolant pump 22delivers coolant through a line 136 to cool the electrical load 5t) andthe alternator 8. The coolant returns through a line 134 from a cooler158 for the coolant. The bearings 76 and 78 for supporting the powershaft 74 are lubricated by the working fluid. The bearing 76 receives aflow of working fluid through a passage 94 leading from the discharge ofthe main pump 14 and leakage from the bearing flows through the turbinehousing out through the turbine exhaust passage 68. The bearing 78 islubricated through a passage 116 which leads from the outlet of thecoolant pump 22. Leakage from the bearing 78 flows into the chamber 126to the inlet of the main pump. The accumulator is arranged to maintain abalance between the coolant system and the fluid system for operatingthe turbine to compensate for iluid leakage, with the entire systembeing sealed.

Thus it will be seen that I have provided an improved power plant whichmeets the objectives and advantages hereinbefore set forth. The featuresof the invention are well adapted to use in the unattended continuousoperation engine of the type operating on the Rankine cycle. Thearrangement of elements which provides for sealed systems` is welladapted to utilizing heat energy from an atomic source and for safereliable continuous operation.

I have, in the drawings and specification, presented a detaileddisclosure of the preferred embodiments of my invention, but it is to beunderstood that I do not intend to limit the invention to the specicform disclosed but intend to cover all modiiications, changes andalternative constructions and methods falling within the scope of theprinciples taught by my invention.

I claim as my invention:

l. A sealed power plant operating on the Rankine cycle comprising, anenclosing housing completely sealing moving parts of the power plant; afirst group of elements located completely within the housing includinga working uid supply chamber within the housing, a Rankine cycle turbinewithin the housing having a rotor carried on a power shaft, acirculation pump mounted on the power shaft, a coolant pump mounted onthe power shaft for circulating cooling iiuid, and an electricalgenerator having a driven element mounted on the power shaft; and asecond group of elements outside of the housing including electricallines leading from the housing, and a boiler outside the housing withlines for Working fluid leading to the housing, said-second group ofelements including no moving parts.

2. A sealed power plant comprising iu combination an enclosing housingfor completely sealing moving parts of a power plant constructed andarranged for operation on a Rankine cycle, a rotary power shaft mountedwithin said housing7 support bearings for said power shaft mountedwithin the housing, a Rankine cycle engine positioned within the housingand connected in driving relation to said power shaft, a -boiler outsideof said housing connected to deliver heated working fluid to said powerplant for operation and to receive working fluid from the power plant ina clo-sed cycle flow, an accumulator chamber within said housingconnected to maintain a supply of working fluid in the boiler forcirculation through the power plant, and conduit means leading from theaccumulator to said bearings for conducting said working fluid to supplythe bearings with working fluid as a lubricant.

3. A working fluid supply system for `a power plant operating under aRankine cycle including an engine, a boiler for supplying heated workingfluid to operate the engine, an electrical generator driven by theengine and an electrical load provided with cooling means supplied bythe generator, the system comprising a sealed accumulator containing asingle unit supply of working fluid, a rst conduit means leading fromthe accumulator and connecting to a working fluid circuit between theboiler and engine for providing make-up Huid, a second conduit meansleading between the accumulator and the cooling means for the electricalload to provide a supply of working luid to cool the electrical load, aworking fluid cooler in the second conduit means between the electricalload and the accumulator to reduce the temperature of the working fluidused for cooling the electrical load, pump means in the second conduitmeans for circulating the Working uid, and means in the first conduitmeans for controlling the flow of make-up control working uid to theboiler.

4. A flow system for working uid for a closed Cycle power plantincluding a housing, a rotary shaft supported on bearings within thehousing, a turbine having a rotor mounted on the shaft, a pump with animpeller mounted on the shaft, a generator driven by the power shaft andsupplying an electrical load, and a 4boiler for supplying heated workingfluid to the turbine rotor, the working fluid system including conduitmeans for conducting the ow of working fluid between the boiler andturbine, an accumulator chamber within the housing containing a supplyof working fluid, a make-up control conduit leading from the accumulatorto said conduit means for a make-up supply of working fluid to theboiler, a coolant fluid conduit connected to the accumulator and leadingto the pump and to the electrical load for cooling the electrical loadwith said working fluid, and a lubricating fluid conduit connected tothe accumulator and leading to a bearing for directing working fluidunder static pressure to lubricate a bearing whereby said working fluidaccumulator provides a single source of fluid for the functionalrequirements of fluid for the power plant.

5. A sealed power plant adapted for operation on a Rankine cyclecomprising a closed housing, an engine having a power shaft withsupporting bearings enclosed in the housing, an accumulator chamberlocated within said housing, a boiler connected to furnish a supply ofworking uid to the engine connected to receive :t return off workingfluid from the engine for heating, a make-up control conduit meansconnected between the accumulator and the boiler for a Supply of make-upworking fluid, `a condenser located between the turbine and the boiler,a circulating pump between the condenser and the boiler for thecirculation of working fluid, and a bypass line between the circulatingpump and boiler leading to one of said bearings whereby said workingfluid is directed to lubricate the bearing.

6. A sealed power plant operating on a Rankine cycle for continuousoperation comprising in combination a power shaft, a mercury turbinehaving a rotor constructed and arranged to be driven by mercury vaporand mounted on the power shaft, a circulating pump for liquid mercuryhaving an impeller mounted on said power shaft, a condenser connectedbetween the turbine and the circulating pump, a -b'oiler connectedbetween the circulating pump and the turbine for converting the mercuryto a heated mercury vapor, an accumulator provided with a chamber forsupplying a make-up control mercury to said boiler and turbine, make-upconduit means connected between the accumulator chamber and the boilerand turbine, an alternator driven by said turbine, an electrical loadelectrically connected to be operated by the alternator and having acooling means, a coolant conduit leading between said accumulator andsaid cooling means for the electrical load for maintaining the load atan operating temperature, a coolant pump having an impeller mounted onsaid power shaft connected in the coolant conduit for circulating saidcoolant, bearings supporting said power shaft, and lubrication conduitmeans connected between said accumulator and said bearings whereby themercury functions as a working fluid for operating the turbine and alsoas a cooling uid for the electrical load and a lubricant for thebearings.

7. A closed continuously operable Rankine cycle power plant comprisingan enclosing housing devoid of moving seals, a power shaft supported onbearings enclosed completely within said housing, a Rankine cycle enginemounted within the housing and in driving connection with said powershaft, an accumulator chamber for containing working uid, a boilerlocated externally of said housing, cooling apparatus located externallyof said housing, openings connecting to conduit means leading from saidhousing and consisting of lines for conducting the working uid betweenthe housing and boiler and between the housing and said coolingapparatus, a static pressure chamber in said accumulator, and anexpansible wall dividing the accumulator chamber for the working fluidand the static pressure chamber whereby static pressure is maintained onthe working fluid within the accumulator chamber.

S. A. power plant constructed and arranged for continuous operation andcomprising in combination an engine for operation under a Rankine cyclehaving operating bearings, a condenser positioned to receive workingHuid from said engine, a boiler located to receive working fluid fromthe condenser and to deliver it to the engine, a circulating pumpconnected between the boiler and condenser for circulating condensedworking Huid, a cooling circuit for cooling elements of the power plant,a coolant circulating pump in the cooling circuit driven by the engineand having operating bearings, an accumulator chamber for working fluidand provided with lines supplying the boiler and engine with make-upworking fluid and supplying the coolant system with working fluid, afirst lubricating by-pass line connected to the discharge of thecirculating pump for the working uid and connected to the operatingbearing for the engine to lubricate the bearing with working fluid, anda second lubrieating conduit connected to the discharge from the coolantpump and connecting to the operating bearings for the coolant pumpwhereby working fluid will lubricate the pump operating bearings.

9. A power plant for isolated sealed continuous self sustained operationcomprising in combination a sealed housing, a power shaft supported onlbearings within the housing and carrying a turbine rotor, a boilerlocated eX- ternally of the housing, a conduit means leading between theboiler and the turbine rotor for operation ofthe rotor with a workinguid, a circulating pump drivingly connected to the operating shaft andpositioned t-o circulate the working fluid through the boiler, an`alternator connected in driven relationship t0 the turbine and totallysealed within the housing, an accumulator chamber located completelywithin the housing for containing working fluid, a make-up conduitleading from the accumulator to supply make-up control Working fluid tothe boiler and turbine rotor, a coolant conduit means leading from theaccumulator to cool the alternator, a coolant pump located wholly withinthe housing and connected in the coolant conduit means for circulatingthe working uid used as a coolant, rotary bearings located wholly withinthe housing for'supporting the power shaft, and lubrication conduitmeans connected to distribute working fluid to said bearings wherebysaid Working fluid acts as a lluid for driving the turbine and as acoolant and as a lubricating uid -for the bearings.

10. A closed cycle integral Rankine cycle engine assembly comprising incombination an engine driving a power shaft supported on bearings, anintake line for Working lluid delivering heatedworking iiuid to theengine for operation under a Rankine cycle, a boiler connected todeliver heated -workingvuid to said intake line, an exhaust line meansleading* from said engine and leading back to said boiler, a by-passline connected to the exhaust line means at a vfirst location andconnected to said bearings for delivering working fluid to saidbearings, a bearing waste line positioned for collecting said Workingfluid from vthe bearings and connected to said exhaust line means at asecond location upstream from said rst location whereby the Workingfluid is utilized for lubrication, and pump means in said exhaust linemeans -between said iirst and second locations for pumping the workinguid from the engine to the boiler and through said by-pass line. v

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